Wash pie pumpkins and cut in half scraping out seeds and strings from inside of the pumpkin. Cut pumpkin flesh into large chunks. In a large stock pot with steamer basket, fill bottom with approximately 1" of water and place pumpkin into steamer. Steam for 20 to 30 minutes, or until pumpkin is soft; drain and allow to slightly cool. Once cool, scoop pumpkin flesh from shell into large mixing bowl and discard shell (note: if properly cooked, pumpkin flesh should easily separate from shell). Using a food processor, purée pumpkin until smooth (this should yield approximately 3 cups of fresh pumpkin purée.)

Preheat oven to 425ºF. In same mixing bowl, add sugar, cinnamon, cloves, allspice, ginger, salt, eggs and evaporated milk. Using mixer, mix well until all ingredients are incorporated. Fill pie crusts with equal amounts of filling. Bake pies at 425ºF for 15 minutes and turn temperature down to 350ºF for an additional 45 to 60 minutes (or until knife inserted in the center of pie comes out clean.) Allow pies to cool before slicing and serving.